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Experiments were designed to assess the cardiac sensitizing potential of Scotchgard Brand Fabric Protector FC-4101 [which contains 1,1,1-trichloroethane (TCE)] under simulated misuse conditions. Beagle dogs were prepared for telemetric monitoring of their electrocardiogram (ECG) and placed in a 290-liter chamber. They were observed for possible effects of inhalation exposure to FC-4101, alone or in combination with intravenous epinephrine (8 and 16 μg/kg) and/or stress induced by a 2-sec blast from an air horn. The effects of inhaled pure TCE with Freon 12 propellant were also investigated. Changes in heart rate consisted of a bradycardia (presumably of reflex origin) due to epinephrine and stress, and a mild tachycardia following exposure to FC-4101 producing a concentration of 5000 ppm TCE in air. Following exposure to FC-4101 producing a concentration of 10,000 ppm TCE in air and following exposure to concentrations of 5000 ppm TCE in air and 10,000 ppm TCE in air with Freon 12 propellant, no tachycardia occurred. Inhalation of FC-4101 did not act synergistically with exogenous epinephrine (8 μg/kg) or endogenous epinephrine released in response to stress to induce cardiac arrhythmias. The arrhythmias induced by 16 μg/kg of epinephrine and stress were not intensified by the concurrent inhalation of FC-4101, 5000 ppm TCE. It is concluded that the simulated misuse conditions utilized in this study, FC-4101 and pure TCE with Freon 12 propellant did not cause cardiac sensitization.

A smoke exposure device delivering marijuana smoke to mice is described. Standardized smoking conditions were achieved with this unit yielding a concentration of 0.123 mg/liter of delta-9-tetrahydrocannabinol in air. A significant (p < 0.05) decrease in locomotor activity in treated animals was seen following the fourth treatment in a 21-day study where animals were exposed three times weekly for 3 weeks. A significant decrease in body weight for marijuana-exposed animals was also noted. In another study, animals were exposed daily for 7 days. Locomotor activity was significantly decreased in marijuana-exposed animals on Days 6 and 7. There was no significant change in body weight. Following removal from the exposure chamber, the marijuana-exposed animals showed transient hyperactivity (1–3 min) followed by a period of depressed activity lasting 1 hr. Some tolerance to the placebo smoke was seen after the fourth treatment in both studies. Cumulative effects were seen following repeated exposures. These preliminary data suggest that inhalation of marijuana smoke will initiate behavioral changes in mice.

Forty male rats were divided equally into four groups. Two groups received oral doses of either 10 or 40 mg/kg/day for 10 days of 1,2,3,4-tetrabromobutane (TBB) dissolved in corn oil. One group received corn oil for the same period. The fourth group received a single oral dose of 0.5 mg/kg of triethylenemelamine (TEM). Each male was subsequently mated with two naive, nulliparous females weekly for 14 weeks. Females were sacrificed on Day 14 of gestation. Statistically significant adverse effects, not dose-related, were elicited by TBB at both dose levels during Weeks 6–13. These effects probably involve spermatozoa that existed as stem cell spermatogonia and gonocytes during the administration of TBB. These data suggest that TBB is not a potent mutagen but may adversely affect male reproductive function and performance.

Pentachloronitrobenzene (PCNB) is an effective, broad-spectrum fungicide. Grains used in animal feeds may contain residues of PCNB. Technical grade PCNB (10% corn oil solution) was added to laying mash and fed to Comet Red and White Leghorn chickens at dietary levels of up to 300 ppm for 16 weeks. The hens were then returned to control diet (clearance phase). The concentrations of PCNB; its impurities, pentachlorobenzene (PCB), hexachlorobenzene (HCB), and tetrachloronitrobenzene (TCNB); and its metabolites, pentachloroaniline (PCA) and pentachlorothioanisole (PCTA), were determined periodically in eggs and excreta, and in various tissues taken at necropsy. Concentrations of PCNB, PCA, and PCTA reached a plateau in tissues and eggs by the second week while HCB and PCB concentrations continued to increase throughout the feeding phase. Excreta were found to contain traces of PCNB, PCA, and PCB. TCNB was not detected in any samples. There were no detectable strain differences in distribution or biotransformation. No effects upon weight gain or egg production were observed nor were there any gross pathologic lesions. During the clearance phase, PCNB, PCA, and PCTA were undetectable by the 16th-week, while HCB and PCB remained at levels > 0.002 ppm through 1 year of clearance. The half-life of HCB was determined to be 90 days. The level of HCB in edible tissues and eggs, extrapolated to their maximum possible steady-state concentration, were determined not to pose a health hazard to humans, when chickens are fed diets containing PCNB at 300 ppm.

Three groups of 10 male rats each were gavaged with 0, 70, or 221 mg hexachlorobenzene (HCB)/kg daily for 5 consecutive days. Ten other male rats received a single oral dose of 0.5 mg triethylenemelamine (TEM)/kg. Both compounds were dissolved in corn oil. Following the last administration, each male rat was allowed to mate with two naive, nulliparous females per week for 14 consecutive weeks. Females were sacrificed on Day 14 of gestation. Their ovaries and uteri were exposed and examined for numbers of corpora lutea and total, living and dead implantations. Mating and fertility frequencies were calculated. TEM elicited typical dominant lethal events. HCB did not. Dose-dependent decreases in the numbers of females inseminated and impregnated were observed.